U.S. patent application number 14/934649 was filed with the patent office on 2016-12-01 for thermoelectric generation device for vehicle.
This patent application is currently assigned to HYUNDAI MOTOR COMPANY. The applicant listed for this patent is HYUNDAI MOTOR COMPANY. Invention is credited to In Chang CHU, Jin Woo KWAK, Han Saem LEE, Seung Woo LEE, ln Woong LYO, Su Jung NOH.
Application Number | 20160351777 14/934649 |
Document ID | / |
Family ID | 57281998 |
Filed Date | 2016-12-01 |
United States Patent
Application |
20160351777 |
Kind Code |
A1 |
KWAK; Jin Woo ; et
al. |
December 1, 2016 |
THERMOELECTRIC GENERATION DEVICE FOR VEHICLE
Abstract
A thermoelectric generation device using engine waste heat
includes: a thermoelectric element including a sheet-type graphite
layer having thermal conductivity; first heat transfer bodies
joined to the graphite layer at intervals and having thermal
conductivity and electrical conductivity; second heat transfer
bodies disposed between the first heat transfer bodies at intervals
and having thermal conductivity and electrical conductivity; first
pellets of a P-type thermoelectric material joined between the
first and second heat transfer bodies alternately with second
pellets of an N-type thermoelectric material. The second pellets
are joined between the first and second heat transfer bodies
alternately with the first pellets. In particular, at least one of
the first pellet or the second pellet is joined in a line-contact
to form an angle with an inclined portion of the adjacent heat
transfer body and to form a surface-contact when the graphite layer
is curved.
Inventors: |
KWAK; Jin Woo;
(Gyeongsan-si, KR) ; LYO; ln Woong; (Suwon-si,
KR) ; NOH; Su Jung; (Seoul, KR) ; CHU; In
Chang; (Seoul, KR) ; LEE; Seung Woo; (Seoul,
KR) ; LEE; Han Saem; (Seoul, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HYUNDAI MOTOR COMPANY |
Seoul |
|
KR |
|
|
Assignee: |
HYUNDAI MOTOR COMPANY
Seoul
KR
|
Family ID: |
57281998 |
Appl. No.: |
14/934649 |
Filed: |
November 6, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 35/30 20130101;
H01L 35/32 20130101 |
International
Class: |
H01L 35/32 20060101
H01L035/32; H01L 35/30 20060101 H01L035/30 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 1, 2015 |
KR |
10-2015-0077053 |
Claims
1. A thermoelectric generation device using engine waste heat,
comprising: a thermoelectric element configured by a sheet-type
graphite layer having thermal conductivity; a plurality of first
heat transfer bodies joined to a surface of the graphite layer at
predetermined intervals and having thermal conductivity and
electrical conductivity; a plurality of second heat transfer bodies
disposed between the first heat transfer bodies at predetermined
intervals and having thermal conductivity and electrical
conductivity; and first pellets of a P-type thermoelectric material
joined adjacent to each other between the first heat transfer
bodies and the second heat transfer bodies alternately with second
pellets, the second pellets of an N-type thermoelectric material
joined adjacent to each other between the first heat transfer
bodies and the second heat transfer bodies alternately with the
first pellets; wherein at least one of the first pellets or the
second pellets is joined with an inclined portion of an adjacent
heat transfer body in a line-contact form so as to form an angle
with the inclined portion of the adjacent heat transfer body at
one-side edge thereof, and said at least one of the first pellets
or the second pellets forms a surface-contact with the inclined
portion of the adjacent heat transfer body when the graphite layer
is curved.
2. The thermoelectric generation device according to claim 1,
wherein the first heat transfer bodies and the second heat transfer
bodies each have a trapezoidal cross-section, and the first pellets
and the second pellets each have a parallelogram cross-section, and
wherein the angle between said at least one of the first pellets or
the second pellets and the inclined portion of the adjacent heat
transfer body is controlled by changing and controlling a slope of
the inclined portion of the adjacent heat transfer body and the
first and second pellets adjacent to each other.
3. The thermoelectric generation device according to claim 1,
wherein the thermoelectric element is attached to one end of a heat
pipe to be surrounded so as to increase a heat transfer
efficiency.
4. The thermoelectric generation device according to claim 3,
wherein a housing receives thermoelectric cartridges each
comprising the thermoelectric element and the heat pipe, and the
housing is divided into a compressing portion at an upper end and
an evaporating portion at a lower end along a length direction of
the thermoelectric cartridges, wherein in the compressing portion,
an exhaust gas inlet and an exhaust gas outlet for flowing and
discharging the exhaust gas are formed so as to flow the exhaust
gas to the thermoelectric element surrounding one end of the heat
pipe, and in the evaporating portion, a coolant inlet and a coolant
outlet for flowing and discharging an engine coolant are formed so
as to flow the engine coolant to another end of the heat pipe.
5. The thermoelectric generation device according to claim 3,
wherein the heat pipe is a rod-type heat exchanger in which a
working fluid is sealed into a pipe portion in a vacuum state, and
the working fluid uses any one material or a mixture of two or more
materials selected from mercury, sodium, lithium, and silver.
6. The thermoelectric generation device according to claim 5,
wherein the pipe portion is made of steel use stainless material.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Korean Patent
Application No. 10-2015-0077053, filed on Jun. 1, 2015, which is
incorporated herein by reference in its entirety.
FIELD
[0002] The present disclosure relates to a thermoelectric
generation device using waste heat of an engine which may generate
electric energy.
BACKGROUND
[0003] The statements in this section merely provide background
information related to the present disclosure and may not
constitute prior art.
[0004] Generally, a thermoelectric generation technique for a
vehicle is a technique of generating electric energy by using a
thermoelectric element which is installed together with a cooling
system on a hot heat source unit (an exhaust system, an engine
unit, or the like) to improve fuel efficiency, and the
thermoelectric element has a characteristic in which electrons move
by a thermal gradient.
[0005] In general, since thermoelectric conversion performance
depends on a unique ZT value (a performance index representing a
thermoelectric characteristic of a thermoelectric material) and an
output is determined in proportion to a difference in temperature
between a high-temperature portion and a low-temperature portion of
the thermoelectric material, a thermoelectric material by
determining a heat source characteristic of an applied portion, a
design of the element, and a system configuration are
important.
[0006] Most of the thermoelectric generation systems that have been
developed for vehicles are applied to an exhaust pipe through which
hot exhaust gas passes, but the thermoelectric generation systems
have failed to obtain a desired high output.
[0007] Currently, in the case of thermoelectric elements and
systems which have been developed for application to the exhaust
pipe, heat of the exhaust gas is not efficiently transferred into
the element due to various heat-transfer resistance factors which
are generated in the elements or which are generated during an
interface joining process to constitute a thermoelectric module or
system, and heat loss to the outside is generated and thus
efficiency is lowered.
[0008] As known, in the thermoelectric element, as the difference
in temperature between the high-temperature portion and the
low-temperature portion is large, the output is increased, and
performance of the entire thermoelectric system depends on heat
exchange efficiency of the cooling system.
[0009] In the case of a thermoelectric system applied to an exhaust
pipe in the related art, a separate water cooling system is
installed so as to enhance cooling efficiency of the
low-temperature portion, and since the water cooling system
includes a coolant, a heat exchanger, a motor, a flow channel, and
the like, a weight and a volume of the system are largely
increased.
[0010] Further, in the case of an exhaust system for a vehicle,
generally, since a difference in calorific value between a front
section which is relatively near to the engine and a rear section
far away from the engine occurs, the efficiency of the entire
system deteriorates in the case of the thermoelectric system
applied to the exhaust pipe disposed at the rear section.
[0011] Meanwhile, in the case of the engine for the vehicle, a high
temperature of 500.degree. C. or more (600.degree. C. in diesel and
800.degree. C. or more in gasoline) is maintained, and in the case
of using an engine coolant, a separate cooling system is not
required, and as a result, the thermoelectric system applied to the
engine is compact and light, and has high output performance as
compared with the thermoelectric system applied to the existing
exhaust pipe.
[0012] In order to apply the thermoelectric element to the engine,
the thermoelectric element does not need to influence a catalyst
activation temperature of an exhaust system disposed at the rear
side of the engine, and needs to be attached to a complicated shape
of the engine. Further, the output needs to be enhanced by
increasing the number of thermoelectric elements which are
attachable to the engine by forming a large attachment area.
[0013] The existing thermoelectric element is configured by a
structure in which metal interconnects are attached to a pair of
insulation substrate in a predetermined pattern and a first pellet
made of a P-type thermoelectric material and a second pellet made
of an N-type thermoelectric material are joined to the metal
interconnects as a pair. Due to heat resistance of a soldering
material for joining the pellets to the metal interconnects or
joining the metal interconnects to the substrate, even though the
thermoelectric material having a high ZT value at the high
temperature exists, there is a limitation to develop the
thermoelectric element which is applicable at the high
temperature.
[0014] Further, since the substrate needs to be electrically
insulated while efficiently transferring heat, a ceramic material
has been frequently used, but due to characteristics of the ceramic
material, the ceramic material is very vulnerable to durability for
vibration, thermal shock, and the like.
SUMMARY
[0015] The present disclosure provides a thermoelectric generation
device using engine waste heat, providing advantages of generating
electric energy by using hot waste heat generated in an engine and
improving fuel efficiency.
[0016] In one aspect, the present disclosure provides a
thermoelectric generation device using engine waste heat,
including: a thermoelectric element including a sheet-type graphite
layer having thermal conductivity; a plurality of first heat
transfer bodies joined to one surface of the graphite layer at
predetermined intervals and having thermal conductivity and
electrical conductivity; a plurality of second heat transfer bodies
disposed between the first heat transfer bodies at predetermined
intervals and having thermal conductivity and electrical
conductivity; first pellets of a P-type thermoelectric material
joined adjacent to each other between the first heat transfer
bodies and the second transfer bodies alternately with second
pellets given below; and second pellets of an N-type thermoelectric
material joined adjacent to each other between the first heat
transfer bodies and the second transfer bodies alternately with the
first pellets, in which at least one of the first pellet and the
second pellet are joined in a line-contact form in such a manner to
form an angle with an inclined portion of the adjacent heat
transfer body at only one-side edge thereof to surface-contact the
inclined portion of the adjacent heat transfer body when the
graphite layer is curved.
[0017] In one form, the first heat transfer body and the second
heat transfer body may have trapezoidal cross-sections and the
first pellet and the second pellet may have parallelogram
cross-sections, and the angle between the heat transfer body and
the pellet may be controlled by changing and controlling a slope of
at least one inclined portion of the inclined portions of the heat
transfer body and pellet adjacent to each other.
[0018] In another form, the thermoelectric element may be attached
to one end of the heat pipe to be surrounded in order to increase
heat transfer efficiency.
[0019] In still another form, a housing receiving thermoelectric
cartridges comprising the thermoelectric element and the heat pipe
may be formed, the housing may be tightly divided into a
compressing portion at an upper end and an evaporating portion at a
lower end along a length direction of the thermoelectric cartridge,
in the compressing portion, an exhaust gas inlet and an exhaust gas
outlet for flowing and discharging the exhaust gas may be formed in
order to flow the exhaust gas to the thermoelectric element
surrounding one end of the heat pipe, and in the evaporating
portion, a coolant inlet and a coolant outlet for flowing and
discharging the engine coolant may be formed in order to flow the
engine coolant to the other end of the heat pipe.
[0020] In yet another form, the heat pipe may be a rod-type heat
exchanger in which a working fluid is sealed into a pipe portion in
a vacuum state, steel use stainless (SUS) is used as a material of
the pipe portion, and the working fluid uses any one material or a
mixture of two or more materials selected from mercury, sodium,
lithium, and silver.
[0021] According to the exemplary form of the present disclosure,
the thermoelectric element is configured in a solid to solid
contact form by using a shape of the pellets and the heat transfer
bodies without using a separate joining (soldering) material or
process for joining on the substrate as a structure without the
substrate, and as a result, the thermoelectric generation in the
high-temperature area such as the engine waste heat which cannot be
used due to a heat-resistance characteristic of the soldering
material used in the existing substrate is possible.
[0022] Other aspects and forms of the present disclosure are
discussed infra.
[0023] It is understood that the term "vehicle" or "vehicular" or
other similar term as used herein is inclusive of motor vehicles in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g. fuels derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example both
gasoline-powered and electric-powered vehicles.
[0024] Further areas of applicability will become apparent from the
description provided herein. It should be understood that the
description and specific examples are intended for purposes of
illustration only and are not intended to limit the scope of the
present disclosure.
DRAWINGS
[0025] In order that the disclosure may be well understood, there
will now be described various forms thereof, given by way of
example, reference being made to the accompanying drawings, in
which:
[0026] FIG. 1 is a diagram illustrating a thermoelectric generation
device according to one form of the present disclosure;
[0027] FIG. 2 is a cross-sectional view taken along line A-A of
FIG. 1; and
[0028] FIG. 3 is a diagram illustrating an unfolded shape before
the thermoelectric generation device is attached to a heat pipe
according to the present disclosure.
[0029] It should be understood that the appended drawings are not
necessarily to scale, presenting a somewhat simplified
representation of various features illustrative of the basic
principles of the present disclosure. The specific design features
of the present disclosure as disclosed herein, including, for
example, specific dimensions, orientations, locations, and shapes
will be determined in part by the particular intended application
and use environment.
[0030] The drawings described herein are for illustration purposes
only and are not intended to limit the scope of the present
disclosure in any way.
DETAILED DESCRIPTION
[0031] The following description is merely exemplary in nature and
is not intended to limit the present disclosure, application, or
uses. It should be understood that throughout the drawings,
corresponding reference numerals indicate like or corresponding
parts and features.
[0032] The present disclosure is intended to cover not only the
exemplary forms, but also various alternatives, modifications,
equivalents and other forms, which may be included within the
spirit and scope of the present disclosure as defined by the
appended claims.
[0033] In the present disclosure, the thermoelectric conversion of
the high-temperature engine waste heat reaching at proximately
several hundred degrees is performed via a structure which does not
require a substrate and a soldering material causing a
heat-resisting temperature. The removal of the soldering material
for interfacial joining contributes to overcoming the problem of
the heat-resisting temperature.
[0034] As illustrated in FIG. 1, a thermoelectric generation device
according to one form of the present disclosure is configured as a
thermoelectric cartridge unit which modularizes a plurality of
thermoelectric cartridges 100, and each thermoelectric cartridge
100 comprises a heat pipe 110 having a rod shape and a
thermoelectric element 120 attached to the lower end of the heat
pipe 110.
[0035] Referring to FIGS. 2 and 3, the thermoelectric element 120
includes a graphite layer 122 having thermal conductivity, a
plurality of first heat transfer bodies 124 and second heat
transfer bodies 126 attached onto the graphite layer 122, and a
plurality of first pellets 128 and second pellets 130 disposed
between the first heat transfer bodies 124 and the second heat
transfer bodies 126.
[0036] The graphite layer 122 efficiently transfers heat of a heat
source (exhaust gas) while preventing high-temperature oxidation of
the thermoelectric element 120 by using a barrier characteristic of
a graphite material, and is formed in a sheet-type which is
flexibly bendable.
[0037] The first heat transfer bodies 124 have thermal conductivity
for transferring the heat of the heat source and electrical
conductivity for electrical conduction and are formed of
hexahedrons having a parallelogram cross section, the first pellet
128 and the second pellet 130 are adjacent to an inclined portion
having a predetermined slope, and a relatively wide surface of
upper and lower surfaces facing each other in parallel is attached
to one surface of the graphite layer 122.
[0038] In this case, the first heat transfer bodies 124 are stacked
and arranged on the graphite layer 122 at regular intervals in a
predetermined pattern.
[0039] The second heat transfer bodies 126 also have thermal
conductivity for transferring the heat of the heat source and
electrical conductivity for electrical conduction, and are disposed
between the first heat transfer bodies 124 at regular intervals,
and are formed of hexahedrons having a parallelogram cross section,
so that the first pellet 128 and the second pellet 130 are adjacent
to an inclined portion having a predetermined slope, and a
relatively small surface of the upper and lower surfaces facing
each other in parallel faces one surface of the graphite layer 122
at a predetermined interval.
[0040] The other relatively large surface of the upper and lower
surfaces facing each other in parallel of the second heat transfer
body 126 contacts the surface of the heat pipe 110 when one end of
the heat pipe 110 is surrounded by the thermoelectric element
120.
[0041] In addition, the first pellets 128 are made of a P-type
thermoelectric material and joined adjacent to each other so as to
be inserted between the first heat transfer bodies 124 and the
second heat transfer bodies 126. In this case, the first pellets
128 are attached to an inclined portion of the adjacent second heat
transfer bodies 126 (alternatively, the first heat transfer bodies)
in a surface-contact form, and only one edge is attached to an
inclined portion of the first heat transfer bodies 124
(alternatively, the second heat transfer bodies) in a line-contact
form.
[0042] The second pellets 130 are made of an N-type thermoelectric
material and joined adjacent to each other so as to be inserted
between the first heat transfer bodies 124 and the second heat
transfer bodies 126. In this case, the second pellets 130 are
attached to an inclined portion of the adjacent second heat
transfer bodies 126 (alternatively, the first heat transfer bodies)
in a surface-contact form, and only one edge is attached to an
inclined portion of the first heat transfer bodies 124
(alternatively, the second heat transfer bodies) in a line-contact
form.
[0043] That is, the first pellets 128 and the second pellets 130
are attached to both inclined portions of the second heat transfer
bodies 126 (alternatively, the first heat transfer bodies) in a
surface-contact form, respectively, and the only one-side edges of
the first pellets 128 and the second pellets 130 are attached to
both inclined portions of the first heat transfer bodies 124
(alternatively, the second heat transfer bodies) in a line-contact
form, respectively.
[0044] Since the first pellets 128 and the second pellets 130 are
attached to both inclined portions of the first heat transfer
bodies 124 in the line-contact form, respectively, an angle .alpha.
is formed between the both inclined portions of the first heat
transfer bodies 124 (see FIG. 3). As a result, when the graphite
layer 122 is flexibly curved to cover the heat pipe 110, the first
pellets 128 and the second pellets 130 surface-contact the both
inclined portions of the first heat transfer bodies 124.
[0045] Accordingly, a surface curvature of the thermoelectric
element 120 may be adjusted by changing and controlling the angle
.alpha..
[0046] Since the first heat transfer bodies 124 and the second heat
transfer bodies 126 have trapezoidal cross-sections and the first
pellets 128 and the second pellets 130 have parallelogram
cross-sections, the angle .alpha. between the heat transfer body
and the pellet may be controlled by changing and controlling a
slope of at least one inclined portion of the inclined portions of
the heat transfer body and pellet adjacent to each other.
[0047] In addition, the first pellets 128 and the second pellets
130 are alternately disposed between the first and second heat
transfer bodies 124 and 126, and PN-junction pairs forming a pair
in the joined form with the heat transfer bodies therebetween are
connected to each other in series. In this case, the heat transfer
bodies simultaneously serve as the substrate for the existing heat
transfer and the conductor for electrical conduction to generate
electricity when the electrons move by a temperature gradient.
[0048] The thermoelectric element 120 configured above may surround
one end of the heat pipe 110 in order to increase efficiency of
heat transfer and heat exchange.
[0049] The heat pipe 110 is a rod-type heat exchanger in which a
working fluid is sealed into a pipe portion (a container) in a
vacuum state, and in order to use the heat pipe 110 at a high
temperature such as engine waste heat, a stainless metal such as
Steel Use Stainless (SUS) is used as a material of the pipe
portion. In addition, the working fluid in the pipe portion uses
any one material or a mixture of two or more materials selected
from mercury, sodium, lithium, and silver according to a
temperature range to be applied.
[0050] When one end of the heat pipe is heated, the working fluid
in the pipe portion passes through a center portion of the heat
pipe which is in the vacuum state, and moves to the other end in
which the working fluid is compressed, and then the working fluid
automatically moves back to its initial position so that heat
exchange is performed by the movement of the working fluid.
[0051] As described above, the thermoelectric cartridge 100 is
formed by the heat pipe 110 and the thermoelectric element 120
attached to the lower end of the heat pipe 110, and the plurality
of thermoelectric cartridges 100 are modularized to constitute the
thermoelectric generation device.
[0052] As illustrated in FIG. 1, the thermoelectric generation
device includes a housing receiving the plurality of thermoelectric
cartridges 110 inside the housing 140, and the housing 140 is
tightly divided into a compressing portion 142 at an upper end and
an evaporating portion 146 at a lower end along a length direction
of the thermoelectric cartridge 100. Hot exhaust gas discharged
from the engine is supplied to pass through the evaporating portion
146 and an engine coolant is supplied to flow into the compressing
portion 142.
[0053] To this end, in the compressing portion 142, an exhaust gas
inlet 143 and an exhaust gas outlet 144 for inflowing and
discharging the exhaust gas are formed, and in the evaporating
portion 146, a coolant inlet 147 and a coolant outlet 148 for
inflowing and discharging the engine coolant are formed.
[0054] The exhaust gas flowing to the compressing portion 142
transfers heat to the thermoelectric element 120 side while passing
through the outside of the thermoelectric element 120 surrounding
one end of the heat pipe 110, and the engine coolant flowing to the
evaporating portion 146 flows into the other end of the heat pipe
110 (a portion which is not surrounded by the thermoelectric
element) to enhance thermal conductivity of the heat pipe 110.
[0055] As a result, the thermoelectric element 120 largely
maintains a temperature difference between an outer side (the
graphite layer and the first heat transfer bodies) receiving the
heat of the exhaust gas and an inner side (the second heat transfer
bodies) receiving the heat of the heat pipe 110 to emit a high
output.
[0056] That is, the heat from the heat source (the exhaust gas) is
transferred to the first pellets 128 and the second pellets 130
through the graphite layer 122 and the first heat transfer bodies
124, and the heat from the heat pipe 110 is transferred to the
first pellets 128 and the second pellets 130 through the second
heat transfer bodies 126, and as a result, the temperature
difference between the outer side and the inner side of the
thermoelectric element 120 is largely maintained.
[0057] In addition, an electrode unit 150 for outputting
electricity generated from the thermoelectric element 120 is
configured at the lower side of the housing 140.
[0058] The electrode unit 150 is electrically connected with the
thermoelectric element 120 so that electricity generated from the
thermoelectric element 120 may flow, and although not illustrated,
the electrode unit 150 includes an electrode terminal for
transmitting the electricity output from the thermoelectric element
120, a DC-DC converter, and the like to be configured as an
apparatus for converting the electricity output from the
thermoelectric element by thermoelectric generation to be used in
an electric field load of a vehicle.
[0059] As such, in the present disclosure, the thermoelectric
element 120 is configured in a solid to solid contact form by using
a shape of the pellets 128 and 130 and the heat transfer bodies 124
and 126 without using a separate joining (soldering) material or
process for joining on the substrate as a structure without the
substrate, and as a result, the thermoelectric generation in the
high-temperature area such as the engine waste heat which cannot be
used due to a heat-resistance characteristic of the soldering
material used in the existing substrate is possible.
[0060] Further, in the case of the thermoelectric generation,
generally, when an interface such as the substrate of the
thermoelectric element is generated, a thermal loss is generated
and thus heat transfer efficiency is reduced. In the present
disclosure, as the structure without the substrate, since the
thermoelectric element 120 is directly attached to the heat pipe
110, which is the heat exchanger, through the heat transfer bodies
126 and the exhaust gas is directly transferred to the pellets 128
and 130 through the heat transfer bodies 124, the heat transfer
efficiency is largely increased.
[0061] Further, when the thermoelectric element 120 is installed on
the front end of a diesel engine catalyst unit, higher output is
possible in that a high-temperature heat source may be supplied at
all times.
[0062] Meanwhile, in the case of removing the angle .alpha. between
the heat transfer bodies 124 and 126 and the pellets 128 and 230 by
modifying the thermoelectric element 120 to configure a flat-type
thermoelectric element, the thermoelectric element is joined onto
the surface of the flat-type heat pipe through a soldering or
brazing process to configure the thermoelectric cartridge, and as a
result, thermoelectric generation is possible in a low-temperature
area of the vehicle in addition to the engine unit.
[0063] The present disclosure has been described in detail with
reference to forms thereof. However, it will be appreciated by
those skilled in the art that changes may be made in these forms
without departing from the principles and spirit of the present
disclosure, the scope of which is defined in the appended claims
and their equivalents.
* * * * *